Rebuilding the Bridge
The Bay Bridge opened to traffic over 76 years ago. It has served as a connection between San Francisco and Oakland, carrying 240,000 vehicles per day. Consisting of 2 sections, an eastern and western portion, the bridge recently has been retrofitted to withstand possible upcoming earthquakes.
- Watch this video to learn about the different possible modes of vibrations: http://physicsandphysicists.blogspot.com/2011/01/structural-physics-of-golden-gate.html
- Learn about the recent retrofit: www.sfgate.com/default/article/Bay-Bridge-made-to-withstand-major-earthquake-4778622.php
Amazing But True
- When the pressure from the wind pushes on the bridge, the bridge must push back with enough force to remain stable.
- The recent retrofit has been done to allow the bridge to withstand an earthquake of a magnitude 6.7 or greater.
- The swaying of the bridge is monitored my motion detectors which relay the information to a command center 2 hours away.
- The new bridge is designed to more like a sling, where the enormous force placed on the cable will be canceled out by the force on the road.
Can You Apply It?
Using the information provided above, answer the following questions.
- In the new sling design, where would the forces be if a 100 ton vehicle was dropped on the bridge?
- In total, how many separate ways can the bridge oscillate?